Protocadherin-15 (PCDH15)

Protocadherin-15 is a transmembrane cell-adhesion protein encoded by the *PCDH15* gene and is essential for normal function in the cochlea and retina. Protocadherin-15 is a member of the cadherin superfamily of calcium-dependent cell-adhesion proteins. It consists of 11 extracellular cadherin repeats, a transmembrane domain, and a unique cytoplasmic domain. In the inner ear, protocadherin-15 and cadherin-23 form filamentous tip links that convey forces to mechanotransduction channels, allowing sound sensation. Its structure allows for flexibility and mechanical gating critical for auditory function. Protocadherin-15 is also essential in retinal cell maintenance. Mutations in the *PCDH15* gene are linked to autosomal recessive disorders, including Usher syndrome type 1F, characterized by deafness, balance problems, and progressive blindness. Variations in the gene can produce a spectrum of phenotypes, from full syndromic presentation to isolated hearing loss. There is currently no evidence of its direct druggability or modulation by approved therapeutics.

Other names

USH1FCDHR15cadherin-related family member 15DFNB23protocadherin-15

Not applicable; no drugs are known to target this molecule directly